Double spring mounted chair



1968 M. BORENSTEIN DOUBLE SPRING MOUNTED CHAIR Filed Nov. 10, 1966 INVENTOR. MARTIN BORENSTEIN BY z i ,1

ATTORNEY United States Patent Office 3,411,822 Patented Nov. 19, 1968 3,411,822 DOUBLE SPRING MOUNTED CHAIR Martin Borenstein, 177 Florence Ave., Oakland, Calif. 94618 Filed Nov. 10, 1966, Ser. No. 593,446 3 Claims. (Cl. 297-294) ABSTRACT OF THE DISCLOSURE The present invention relates to furniture and particularly spring suspended furniture where the back is mounted on curving parallel spring members extending without interruption to under the forward portion of the seat where they are mounted in spaced relation upon flat spring members which contact the floor and where the mounting means is adjustable separately both as to attitude of the seat and as to resilience of the spring mounting. The seat is mounted in cantilever suspension, without any support at the forward portion.

So much has been done with furniture that it is very difficult to present an original concept, but it is believed that the present structure does so, providing many features which have been attained in some degree by other structures but not in the same manner or means.

Amongst the features of the present invention are its simplicity providing a compound spring action for complete comfort of the user, in addition to safety and stability.

Another feature of the invention is the provision of a rocking chair effect without rockers.

Still another feature of the invention is the adjustment of the seating pitch which can be made quickly by anyone with the aid of a spanner wrench.

Another feature of the invention is that it provides a piece of furniture of modern design which is simple and clean-cut as well as being unusually attractive.

Further objects are to provide a construction of maximum simplicity, economy and ease of assembly and disassembly, also such further objects, advantages and capabilities as will fully appear and as are inherently possessed by the device and invention described herein.

The invention further resides in the combination, construction and arrangement of parts illustrated in the accompanying drawings, and while there is shown therein a preferred embodiment thereof, it is to be understood that the same is illustrative of the invention and that the invention is capable of modification and change and comprehends other details of construction without departing from the spirit thereof or the scope of the appended claims.

Referring to the drawings:

FIGURE 1 is a side elevational view of a. chair embodying the features of this invention;

FIGURE 2 is a rear perspective view of the chair shown in FIGURE 1;

FIGURE 3 is a side elevational view in fragment on a larger scale, showing the structure of the spring mounting; and

FIGURE 4 is a side elevational view of a footstool which is a companion piece for the chair of FIGURE 1 made precisely on the same structural improvements and with the same structuralconsequences.

Referring now to FIGURE 1 and using the reference numerals which designate like parts in the several views, the chair of the present invention has a seat 10 which may be plain or upholstered as indicated in FIGURE 1 and has a curved back 11 which again may be plain or upholstered as shown. The curve of the back 11 is a smooth clean curve which follows the orthopedic requirements for full back support when a human being is seated. The seat 10 and the back 11 are joined to make a unitary structure which is well calculated to support any weight which the chair might receive, plus the usual margin of safety. The best appearance of the chair is to have the structural requirements hidden by the upholstery or covering as shown in the drawings. The chair is supported upon two flat leaf spring members 12 and 14 at either side. The leaf spring member 12 is a flat piece extending from just behind the front edge of the chair seat to just ahead of the top of the chair back 11. The pair of these members 12 are the only portion to touch or contact the floor or other support for the chair. The spring leaf member 14 at its forward end is spaced above and coplanar with the member 12 and runs parallel thereto for a distance from the front and then at point 15 it is bent upwardly assuming the full curvature of the chair back 11. It is fastened to the back of the chair frame in any suitable manner but is shown to be fastened here with screws 19 at spaced intervals along its length which may either have their finished heads project outwardly from the leaf spring 16 as shown, or have them countersunk inwardly so that the heads are flush with the outer surface of the leaf spring.

Referring to FIGURE 3, it will be observed that the flat leaf spring member 12 is secured to the leaf spring member 14 by means of machine screws 20 which pass through concentric holes 17 and 18 respectively, and through a jam nut 21 which acts as a spacer. The machine screw 20 is threaded and is secured in position by the spanner nut 25. It will be observed that in both instances the machine screw 20 has a head which fits exactly the countersinking so that the head is not protruding from the surface which contacts the flooring or other support, but is flush therewith. The spanner nut 25 is tightened in position by a spanner wrench which has a projection engaging in the countersunk hole 26.

At the forward end the machine screw 20 passes through concentric holes 17 and 18 respectively, and through a jam nut 22 therebetween. The jam nut 22 is merely to limit the motion and obviously can be changed to various sizes although the height here is shown to be approximately one-half of the distance between the two pieces of metal. In order to secure a proper return and stabilization around the jam nut 22 there is a spring member 23 which supports the upper plate 14. The spanner nut 24 is turned to hold the position of the member 14 in conformity with the adjustments of the spanner nut 25.

Referring to FIGURE 4, the footstool shown therein has the same seat 29 but a shorter back or footrest 30. Here again the seat 29 and the footrest 30 can be made either plain or with upholstery as shown in the figure. The flat leaf spring member 12 is substantially identical with that already described but the upper spring member 31 after it passes the point 15a is in only a very slight curve. Its manner of attachment and structure is precisely that described in connection with FIGURE 3.

It will be observed that when a person seats himself in the structure shown in FIGURES 1 and 2, any pressure on the back will cause the leaf spring 16 to flex rearwardly with the fulcrum at point Y. It then tends to raise the front end of the entire spring assembly so that at least four separate springs are activated. The two obvious ones are the flexing of the spring backwards and the compression of the spring 23. The other two spring movements are not quite as obvious. The action of the upper leaf spring performs as a fulcrum at point Y and therefore tends to lift the entire assembly at the forward end and raise the forward end of the member 12 off of the supporting surface. This then produces a spring action in the member 12 to return this structure to full support on the floor. While these movements are described in rather severe terms, the consciousness of the user reflects only the back and forth movement similar to a rocking chair which can be made into a pattern by asserting pressure with the feet against the back at intervals as is done with a rocking chair.

Without any change in the manner of operation the seating pitch and reclining action may be quickly changed to suit the individuals posture and preference. The chair is adjusted in two ways. One by turning the two front spanner nuts in a counterclockwise direction to attain additional reclining action. The second is that to attain the more upright seating posture the rear spanner nuts may be loosened and additional washers can be inserted above the jam nut 21 which raises the fulcrum. It will be observed that in any forward movement the fulcrum would be at point X and in any rearward movement the fulcrum would be at point Y.

It will be observed that the structure of the footstool shown in FIGURE 4 is substantially identical with that described for the chair and the action of the two leaf spring members 12 and 14 are precisely that described in connection with FIGURE 3. It has the same action and the adjustments can be made in the same manner. The footstool obviously has the same spring-like qualities and can support a person easily in the same manner as described for the chair.

It will be seen that all of the advantages described and many others inherent in the structure are accomplished by this arrangement of elements.

S wmmary The invention may be summarized to cover a spring mounted chair wherein the seat and convexly curving back are made into a unitary structure. The chair is supported from each side of the back by a ;pair of flat leaf spring members suitably curved to conform to the curve of the back and extending downwardly terminating in a bent portion parallel to the floor with the seat in cantilever suspension thereover. A second pair of leaf spring members position the chair on the floor, adjustably joined only at their forward ends with the coplanar fiat portions of the first leaf springs.

I claim:

1. A spring mounted chair having a seat and convexly curving back formed into a single unit, a first pair of fiat springs curved to conform to the curve of the back and mounted thereon at the rear on each side of said back with cantilever suspension of the chair seat thereover, said springs extending to adjacent the floor level being bent to a flat horizontal plane parallel to the floor at their forward terminating ends under the forward portion of said seat, a second pair of flat leaf springs secured to the first pair of fiat springs at their parallel forward ends and vertically coplanar therewith, adjacent the forward end but spaced from each other, for resting the chair on the floor, and resilient adjustable screw means for changing the parallel relationship of the mounting at the forward terminating ends of said flat leaf springs to change the seating pitch :and the springiness of said chair.

2. The chair of claim 1 wherein the curve of the chair back is carried continuously to the place of the forward flat bend and wherein the first and second pairs of leaf springs are separated by adjustable spacer washers and nuts.

3. The chair of claim 2 wherein the forwardmost connectors of the first and second pairs of leaf springs are separated by a spacer nut of a lesser height than the separating distance and Where the adjusted separation is maintained by a compression spring.

References Cited UNITED STATES PATENTS 1,433,720 10/ 1922 Hendrickson 248-392 2,313,559 3/1943 Larson et a1 297302 2,411,125 11/1946 Borsheim 248-377 X 2,528,607 11/ 1950 Preising et al. 248-377 2,586,951 2/1952 Johnson 297-302 X FOREIGN PATENTS 43,838 6/1934 Fnance.

731,245 5/1932 France.

743,388 1/1933 France.

558,774 12/ 1929' Germany.

557,563 2/ 1957 Italy.

JAMES T. MCCALL, Primary Examiner. 

